METHOD AND APPARATUS FOR OBTAINING THE TOPOGRAPHY OF AN OBJECT

A system, method, and apparatus for obtaining the topography of an object using computer analyzed rasterstereographic images. The object may be nontransparent and diffusing, or it may be transparent and nondiffusing, such as cornea. Rasterstereographic images of a cornea are produced by staining the cornea with a fluorescein solution which projects a light and dark line pattern onto the cornea through a grid. When obtaining the topography of a cornea, several different filters are used for producing and obtaining a grid image. An image processor uses unique software to store and analyze data extraced from the grid pattern. A video camera, an illuminator, the filters, and the grid may be mounted on a microscope. One embodiment uses a grid with vertical lines. Another embodiment uses a grid having intersecting horizontal and vertical lines for exhibiting surface details in a two-dimensional x-y plane. A computerized method and associated apparatus uses the data from the x-y plane to determine the projected grid intersection points on the surface of the cornea by intersecting a light ray formed by the grid intersection points on the actual grad in the projected system with a light ray formed by the grid intersection points of the image in the camera system.